Vehicle suspension



July 1s, 195o G. s. PANE 2,515,379

VEHICLE SUSPENSION Filed April 18, 1947 2 Sheets-Sheet l GILBERT 5. PAlNF.

INVENTOR.

BY ai l @l 4 ATTORNEY July 18, 1950 Filed April 18, 1947 G. S. PAINE VEHICLE SUSPENSION 2 Sheets-Sheet 2 GILBERT 5. PAINE INVENTOR.

BY f Z 2 ATTORNEY Patented July 18, 1950 UNITED STAT ES PAT ENT* OFF ICE.

VEHICLE sUsrEN-s'IoNI Gilbert S. Paine, Dallas, Tex.vr Application April 18; 1947,. Serial No.v 742,249 v '7 Claims'. (Cl. 28d-533.4)v

This invention relates to new and useful. improvements in vehicle suspensions, and more, particularly to suspensions for trailer frames.

One object of the invention is toprovide an improved vehicle suspension which is so. arranged that-the frame remains substantially level for all.

load.- conditions.

A particular objectv of the. invention to. provide" arr-improvedy vehicle suspension. which is so arranged that the center of gravity of the vehicle is lowered nearer the ground wheny aheavy load is mounted onthe vehicle.

Ai further objectv of the invention is. to provide inav vehicle suspension, of. the character described, means for effectively changingi the positionof the center: of gravity of the. load on the vehicle with respectto the wheels of the vehicle, whereby the. wheel loading is more evenly ad.- justed.

Another object of the invention is to provide a vehicle. suspension,v particularly adaptedv` for two-wheel trailers which are arranged to be hitched. tothe rear of tractors, automobiles,A or other machines, including an offset axle arrangement. which permits the center of gravity of, the trailer toy be lowered under heavy loadingv conditions and which providesfor the transfer of. a portion, of the heavier load to the rear. wheels of the `tractor or automobile. by effectively changing the position of the center of gravity of. the. loadv with respect to the trailer wheels.

A- particular objecty of the invention is to provide` animproved two-wheel trailer, adapted. to be connected to. the rear of a tractor or. automobile. so. as.- to` be drawn thereby, and. wherein. the axle ofthe trailer is formed with. an offset or crank permitting the trailer frame to beraised or lowered. with'l respect4 to the center ot thev trailer wheels, the trailer. having; a hitch which, is automatically operable in conjunctionwith the oft-set. axle to; maintain the.v trailer framev and body in a level position for all load conditions.-

Still. another object of the invention is to provide a trailer ofl the character describedwherein the frame'may be" moved to and locked I ing conditions; said locking means also rendering inrvarious adjusted positions with respect tothe.

center. of. the: wheels,v whereby the center of.. gravity of the trailer andl the load carriedx therebymay be, raised'. or lowered. with respect to: thecenter ot the trailer wheels;`

A.. still. further object of. the. invention isL totheresil'ie'nt restraining means inelective, if desired.

Yet another object of the invention is' t0 provide a trailer suspension of the character described wherein thev trailer hitch and the offset axle of the trailer connected with the hitch permit the load carried by the trailer to act as a shock vabsorber when the tractor or automobile is started suddenly, whereby spring shock absorbers are substantially eliminated.

Additionalobjects and advantages of the invention will readily beA apparent from the reading of the following description of a device constructed in accordance with the invention, and reference to the accompanying drawings thereof, wherein:

Figure; l is aplan View of a trailer frame suspension constructed in accordance with the invention,.

Figure 2` .is al longitudinal vertical sectional View taken on.r the line 2-2 of Figurev 1, and showing. the trailer frame in normal elevated position,

Figure. 3A is a view` similar to Figure 2, showing thetrailer frame ina lower loaded position,

Figurev 4' i`s a fragmentary view of one end of the movabl'el cross-bar connectingA the wheel cranks or offset. axles with the trailer hitch.,

Figure 5y is a view partly in elevation and partly in section, illustrating the tie-rods locking the offset axle stubs in adjusted xed position with respect to the frame,

Figure 6`isv a plan. view ofl the rear portion of the' vehicle illustrating the adjustable mounting. for the. axle shaft,l and.`

Figure 7` is a transverse vertical sectional view takenon the lineA 1--1 of Figure 6.

In. the' drawings, the numeral l designates generallyV a. substantially rectangular vehicle frame havin'gparallel. longitudinal side frame members. II`, a rear cross-member l2 and a iront trame cross-member I3. The frame members are preferablyformed of channel irons having their anges-directed inwardly, but may be offany suitablev desired. material. A pair of. channel members Iiiorming inwardly extending or converging forwardJ projectionsof the side members ll. oi' the frameprovide. a yoke or support I5 for a trailer hitch member I'6 by means of'whi'ch the trailer may be connected to a rear draw bar` (not shown). rcarriedlby a tractor, automobile orother suitablemachine for pulling the trailer.

Anelongat'e axle shaft t1. is rotatably mounted iii-bearings` Iii wl'iichr are secured to the under si'de of the". rear. portion of the longitudinal side fiame. members. of the trailer. A. crank throw membenpreferably in the form of a flat circular disc I`9`, is secured at each endl of. the. axlev shafti I.1.`,`,saiddiscs. being secured toi the shaft near their peripheral edge and positioned at right angles to the axis of the shaft in such a manner that the center of each disc lies in a plane extending through the longitudinal axis ofthe laxle shaft, whereby `the centers of thediscs are in alignment. One of a pair of stub axle shafts whereby the frame will not tilt toward one wheel or the other because of an unbalanced lateral 29 has its inner end secured at the center of each the` centers of the wheels may 'be moved from an'elev'ated position, such as is shown in Figure 2,v

to a `lowered position,'such as is shown in FigureB, whereby vthe center of gravity of the trailer and the load carried thereby may be shifted from the elevated position to the lowered position to' increase the stability of the loaded trailer.

rlor resiliently maintaining the trailer frame in the vnormal elevated position of Figure 2, each of la pair of connecting or pitman rods 2 5 has one end 'pivctally connected to the peripheral edge' portion of one of the discs I9 by a bolt 26 extendingv through one of a plurality of space d openings 2l formed near the peripheral edge of said discspaced from the axle shaft I'l, and has its other end pivotally connected to a cross-bar 29 which extends transverselyl of the trailer frame andisr movable in a stirrup strap 30 secured to the under side of said frame for guiding the movement of the cross-bar. For resiliently urging the cross-bar toward the front end of .the frame, itis preferable thatv elongate helical ten--` sion springs have one end connected to thev cross-,bar 29 and their other end connected to one of a pair of draw .plates 35 which'm'ay be adjusted in position by elongatethreaded crank screws 31 rotatably mounted in a transverse sup.

port channel 38 secured to the'under side of the channel members I4 forming the yoke l5 and threaded in to said draw plates`. It will readily be seen that the crank screws 31. may berotated to'adjust the position of the:v draw plates. 36,1

whereby the tension of the springs 35 maybe adjusted as desired. The .springs act to resiliently restrain the cross-bar 29 in the forward positionshown in Figures land 2, whereby the stub axles are swung downwardly toward the front of the trailer frame lll and the frame is maintained in an ele-` vated position. However, when a load is placed loading condition.

An elongatedraw-bar 40. has one end connected substantially centrally of the cross-bar 29 and extends forwardly therefrom, through an opening in a guide lug 4I secured to and depending from the center of the under side of the front -frame cross member I3, to a point near the ltrailer hitch I6.

The trailer hitch member I6 is in substantially theform'of abell-crank, having its center pivoted on a bolt 42 extending through the forward ends of the channel members I4 of the yoke l5,

vlli

and having a url versalballtype connection 43 on one-arm by means'V of which the hitch member may be securedto .a socket (not'sh'own) car ried by the draw-'bar of the tractor,` automobile or otherr pullingv machine. v'The other arm 44 of the 'crank-like hitch'member isfconn'ected'by means of a link member 45 to the draw-bar 4U, whereby movementof the cross-hairV "29 causing longitudinal movement-of theA draw-bar is transmitted through the dratvbar" and the link 44 to the hitch member I6. v v

In use, the ball 43 ofthe hitch member is'connected to the draw-bar (not shown) "of the trac# tor. or automobile in the customary manner; the

` position of the hitch member, with v the trailer not upon the frame l0, the load will cause the frame to be moved downwardly, and the wheels on the stub axles 29 to swing upwardly about the center ofthe axle shaft I1 toward the position illustrated in Figure 3, pullingthe cross-bar 29 towardV the rear of the frame against theforce of the springs 35. j

It is to be noted that, since the trailer wheels are mounted on the offset stub axles and must move together because of their rigid inter-connection, any force tending to move oneside of4 the trailer frame downwardly withrespect to the wheels will likewise move the other side of the frame downwardly the same distance. Thus, the offset or'crank-like wheel mounting provides forV maintaining the frame of the trailer parallelto the elongate axle shaft l1 for all load conditions;

loaded, being such'that the 4frame vlll of the trailer is substantially level when the connect-v ing ball 43 is secured tothe draw-bar of thetractor or automobile.V So long as the trailer re mains unloaded, it is obvious that the frame IU will remain in the level position. However, when a load is placed on the frame of the trailer, the framewill move downwardly, swinging the stubaxles 29 andthe disc-like crankthrow'members i9 upwardly through an arc toward the rear of the frame. This swinging of the crank throw' members causes the connecting rods 25 to move the cross-bar 29 toward the rear of the trailer against the tension'force ofthe spring 35; and as the cross-bar is moved rearwardly, the drawbar 46 is likewise moved longitudinally toward the rear of the trailer. Rearward movement of the draw-bar 49`pulls the linkl 45 `toward the rear of the trailer and swings the-arm y44 Yof'thehitch member I'about the blt'42 toward the position illustrated'in Figure 3. Such movement of the,

hitch member swings thel vconnecting ball 43 through Hanarc about 4,the bolt 42 toward the position illustrated in Figure 3, whereby the front end of the trailer frame Hl isalso lowered and the frame is maintainedin substantially horizontal position regardless ofthe load placed on said frame. v

j; It will be seen, therefore, that the arrangement of the connecting rods 25, the cross-bar 29, the draw-barili), the linkY 45,' and the lengths of the arms of the hitch memberr I6, is s uch that when the stub axles 29 are swung through an arc aboutthe elongate axle shaftA Il, the hitch connecting ball 43 is likewiseswung through a cor'-- responding arc aboutthe b'olt'f42 tomaintain the trailer frame in a level position.v 'The height of the connecting ball 4 3 above the groundv remains substantially constant regardless of the level to which the'framelll of the trailer is depressed by the 10aa carriedby said frame, and the height of the stub axles "20 abovetheground obviously remains'-constant regardless of the position of the trailer frame. Therefore, the trailer fram'e, in effect, is supported ,ancl4 swungv from the `stub axles 20 'and the-connecting ball-43 r4on link/slof(l endconnected to the-.cro'ss-barfand having-its' other end connectedI with the-swingable lhitch member whereby movement of the offset-:axle end# portions causes .corresponding "swinging movement 1 of Y the f 4swingable hitch l memberV to maintainfthel frame substantially` level during adjustment -in'height 'o`f the'frame above-theground. Q f' 4 lf 2. A vehicle suspension including,"aframe, an` axle 'c'arrie'd by the v'frame and having aligned swingable -v oiset A wheel carryingr end portions whereby' the 'frame may undergol adjustmentsl in height above the `4ground, ai swingable hitch memberv carried `by the frame and-"adapted to be connected to afpulling machine, and a linkage' connecting the 'offset' axle end portions and the swingable hitch `member so that-movement ofl the axle end portions causes corresponding swinging movement of the hitch member, whereby the frame 'is automaticall-y maintained substantially levelwhen the-offset axle end portions swingtolower the center of gravity of the frame-Yi Y 39A vehicle suspension including, a frame, al wheelcarrying axlehaving'integral offset wheel carrying end portions-swingable about the longitudinal axis'of the'axle, a vhitch member-adapted; to be connected to a pulling machine and swingably 'carriedby the'frameso as to be movable up-v wardly and downwardly with 'respect to said" frame, a linkage vconnectingjthe swingable hitch member with the offset end portions'of the axle for causing automatic cooperative movementvof the axle end portions with the hitch member, wherebya horizontal pull exerted Vby the pulling machine on the hitch membercausing movement ofthe'hitch' member in a vertical direction causes corresponding movement of the offset *axle-end portions tending to yraise the frame against the weight of the load thereon so that the load on the frame-acts as a shock absorber' reducing thev shock of'starting movement of the trailer under heavy load.v

'4.' A vehiclesuspension including, a'frame, anl axle" shaft carriedV Iby the frame vrotatable `about` its axis-and 'having aligned oisetwheel supporting lend portions swingable in "an arc about 1 the axis of the shaft wherebythe vframe may undergo' adjustment in height abovethev ground, a cross-j bar movably vcarried bythe fifameand connectedv with the `offset-axle end portions so' as to be moved` whensaid endfportions'swing in an arc, Aaf'swing able hitch member for connecting the frame with a pulling machine, a draw ibar havingv one end connected tothe cross-'bar and having'its other e'nd connected with the swingable hitch member whereby movement of the offset axle end portions causes corresponding swinging movementr of 'the swingable hitch'member to Vmaintain the frame substantially level during adjustments inyheight` ofthe frame abovei the ground, and adjustable yieldable means restraining the offset axle-end portions against swinging movement ywhereby the force opposing swinging movement of said oiset end portions may be varied and controlled.

5. A1 'vehicle suspension including`,va frame, a cross member movably mounted-on the frame and adjustable longitudinally of the frame, an axle shaft carried bysaid crossmember lso ,as Ato be adjustable in position .longitudinally of the frame*` when the crosszmemberfis moved' with'respect to the'frame, saidaxle :shaft being rotatable about its axis'a'nd having aligned` offset wheel supporting end portions swingable inl an arc aboutV the axis of the shaft,whereby the, frame may undergo adjustment' inheightabovethe ground, a cross.

bar lmovablycarriedby `the frame and spaced from-'the' axleand cross member, means connectingsaid'cross-barwith the offset' axle end portions whereby said cross-bar is moved longif" tudinally Aof the frame whenisaid end portions swingv in an arc rabout the axis of the axle, a swingable hitch memberA for connecting the frame with'a pullingmachine, a draw bar having one end connected to the cross-bar and having its Lother end'connectedk with the swingable hitch member whereby movement of the offset axle end portions causes corresponding swinging movement of the swingable hit'ch'member to maintain` the 'frame' substantially 'level during adjustmentA in height ofthe frame above the ground,

and resilient means connected with the frame and with the movable cross-bar for restraining arcuate swinging movement of the onset axle end portions whereby the frame is normally resiliently restrained in elevated position and may move to a lowerposition when a load is carried by the frame, said resilient'means resisting such lowering movement of the'frame, the adjustable cross member providing for selective adjustment of the position of theaxle shaft with respect to the frame to accommodate varying conditions of load, whereby the arc of movement of the onset axle end portions may be properly positioned with respect to the frame and the swingable hitch member to provide for desired proportioning 'of the load upon the axle and the hitch member.1-'W

-6.A A vehicle suspension of the character set forth-in claim l wherein, resilient means is connected with-the'l frame ,and the onset axle end portions for restraining such offset axle end portions againstswinging movement, and means is provided for adjusting the force exerted by the resilient restraining means,'whereby the force opposing swinging of theoiset axle end portions may be varied and controlled.v

7; A vehicle suspension including, a frame, a wheel carrying axle havingswingable offset wheel carrying end portionls,"ar swingable hitch member carried bythe frame and adapted to be connected toca pulling machine for adjustably supporting one endof the 4f'ramathe offsetv axle end portions swinging toward the rear en d of the frame when a loadis mounted onthe frame whereby the center of the load is shiftedl with respect to the wheels carried by the axle end portions to effectively transfer an increased portion of the load to thepulling machine, and link members connecting the oifset axle end portions with the swingable hitch member so that' swinging movement of the axle end portions causes corresponding swingingmoveme'nt of the swingable hitch member to automaticallyy maintain the frame substantially level during adjustments i-n height of the frame above the ground.

' IGILBERT S. PAINE.

REFERENCES CITED '.The following references are `of record in the le of patent:

Number Name Date 1,691,583 y vPearson Nov. 13, 1928 2,059,205 "Bufngton Nov. 3, 1936 2,179,477 Berendsen Nov. 14, 1939 2,196,338 vMcDaniel Apr. 9, 1940 2,227,762 -Ronning Jan. 7, 1941 2,297,992 Swim f Oct. 6, 1942 2,365,884., VKucera"` Dec 26,1944 

